The present invention relates to a technique for manufacturing a semiconductor device, and in particular, to a technique that is effective when applied to the manufacture of a semiconductor device using an exposure apparatus in which exposure light is radiated onto a substrate via a projection optical system and a liquid.
Exposure apparatuses are required to have higher resolution year by year, and with this trend, it is promoted to make the wavelength of exposure light to be small and the aperture of a projection optical system to be large. However, there is a problem that the above measures make a depth of focus to be small although they improve the resolution. Accordingly, an immersion exposure method is under consideration in recent years, in which exposure is performed by forming, between the lower surface of a projection optical system and a substrate in an exposure apparatus, an immersion area filled with immersion water, such as pure water or an organic solvent each having a refractive index higher than that of air. In this method, the wavelength of exposure light can be substantially made small and a depth of focus can be made larger in comparison with that in air.
For example, Japanese Unexamined Patent Publication No. 2005-347617 discloses a technique in which supply and recovery of a liquid can be efficiently performed, by making a nozzle member provided in an immersion exposure apparatus have a structure including a laminated body formed of a plurality of members, and by providing a porous area in at least one of the of members forming the laminated body, thereby maintaining the strength of the nozzle member and improving a degree of freedom in design. In addition, an aspect, etc., is described in which, by making the supply amount of the liquid to be large prior to exposure of a substrate, bubbles that may have been adhered to, for example, the liquid contact surface of an optical element, the lower surface of the nozzle member, or the surface of the substrate are removed with the momentum of a flow of the liquid, and thereafter an optimal supply amount of the liquid is supplied to an immersion area when a substrate is exposed.
Also, Japanese Unexamined Patent Publication No. 2009-21498 disclosures an immersion exposure apparatus including: a first supply port for supplying a liquid; an immersion member that has a first surface arranged in at least part of the periphery of the light path of exposure light and is capable of holding the liquid supplied from the first supply port between an object movable with respect to the first surface and the first surface; and a dryness prevention device for preventing the first surface from being dried.
Also, Japanese Unexamined Patent Publication No. 2005-223315 discloses an immersion exposure apparatus in which a failure, occurring due to a fluctuation in the pressure of a liquid (e.g., deformation of a substrate or a substrate stage, displacement of a projection optical system, or occurrence of vibrations), is solved by regulating, with a pressure regulation mechanism, the pressure of the liquid supplied from a liquid supply mechanism.
Also, Japanese Unexamined Patent Publication No. 2005-286286 discloses an immersion exposure method in which deformation of a substrate or a substrate stage and occurrence of vibrations are prevented by setting the affinity of the surface of the substrate with respect to a liquid such that the force of the liquid on the substrate exerting on the substrate is reduced.